Tourniquets are commonly used in modern hand surgery to provide a bloodless field. Conventionally, a pneumatic tourniquet cuff is applied around the upper arm and tightened to restrict the blood flow to the hand being surgically treated.
A number of drawbacks occur by use of the aforesaid pneumatic tourniquet cuff applied around the upper arm. For example, when the tourniquet is applied around the upper arm under regional block anesthesia (e.g., axillary, supraclavicular or Brier IV block), patients frequency experience pain under the tourniquet especially if the anesthesia is incomplete. Furthermore, since the tourniquet should be applied high on the upper arm to avoid injury to the radial nerve, pain is also experienced by the ischemia and the pressure against unanesthetized tissue high in the upper arm. As the pain increases, the only remedy other than deep sedation or general anesthesia is to release the tourniquet which floods the surgical field with blood causing difficulty in completing the surgery. Another disadvantage of the upper arm tourniquet is the possibility of distal migration or movement on the arm. Although a rare occurrence, if unnoticed (since the upper arm tourniquet is completely covered with surgical sheets and drapes), such migration of the upper arm tourniquet can cause nerve damage, especially to the radial nerve.
Preservation of active movement of fingers is crucial in certain procedures, such as tenolysis, to observe the adequacy of the surgery. Such preservation of active movement is not easily obtainable with an upper arm tourniquet and major regional block or general anesthesia since the muscles are paralyzed from the anesthesia. Furthermore, in many cases, the major regional block anesthesia of the types mentioned above are to allow the use of the upper arm tourniquet since the tourniquet causes significant pain without anesthesia. Although rare, complications resulting from these major regional block anesthesia can be detrimental.
Another problem associated with the conventional pneumatic tourniquet cuff applied around the forearm is the inability of such a cuff to adequately restrict blood flow through all four major arteries within the forearm. It is particularly difficult to restrict blood flow through the anterior and posterior interosseous arteries which are hidden in a "valley" between the radial and ulna bones.